1. Field of the Invention
The invention relates to apparatus and method for the concentration of a liquid by evaporation.
2. Description of the Prior Art
U.S. Pat. No. 4,220,193 illustrates a heat exchanger of the type in which a liquid being treated is passed through a bundle of parallel vertical riser tubes which are connected at their upper and lower ends to upper and lower tanks respectively, and in which a granular mass (i.e. a mass of particles) is present in these riser tubes and in the tanks and in operation is fluidized by this liquid. The heat exchanger is described as being intended for use as a liquid/liquid heat exchanger, and there is no suggestion of evaporation of the liquid flowing through the vertical riser tubes. In the invention below the basic idea is that the heat exchanger should be utilised as an evaporator/concentrator.